Many eating disorder programs have noted a marked increase in the number of teens who previously were obese or overweight but who now show early signs of developing eating disorders. In their attempt to lose weight the adolescents may have come to rely on unhealthy and unsustainable methods such as skipping meals or using diet pills or laxatives.

Some who reach normal weights for age and body size also may develop medical and psychologic characteristics similar to teens with classic anorexia nervosa. They may present to the pediatrician with signs of medical instability that can include severe bradycardia (slow heart rate) or orthostasis (postural hypotension).

The new guidelines were developed to address the connection between obesity prevention and eating disorders in teenagers, to provide pediatricians with evidence-informed tools for identifying behaviors that predispose obesity and eating disorders, and to provide guidance about obesity and eating disorder prevention messages.

“This is a dangerous category of patient because they’re often missed by physicians,” said Dr. Neville Golden, lead author of the new guidelines, in a news release. Golden is a professor of pediatrics at the Stanford University School of Medicine, chief of adolescent medicine at Lucile Packard Children’s Hospital Stanford, and a physician with the hospital’s Comprehensive Eating Disorders Program.

“At some point, these patients may have had a real need to lose weight, but things got out of control,” Golden said.

According to Golden, about 40% of patients in eating disorders treatment programs fit the easy-to-miss category of overweight dieting teens who are at risk of severe health issues.

The new guidelines incorporate strategies that pediatricians and parents can use to help teenagers avoid both obesity and eating disorders. The guidelines can also apply to all teens, not just those with weight problems.

Three recommendations focus on behaviors to avoid: parents and doctors should discourage dieting, skipping of meals, and the use of diet pills. Instead, they should encourage and support the implementation of healthy eating and physically active behaviors that can be maintained on an ongoing basis.

Two recommendations emphasize behaviors to promote: parents should encourage more frequent family meals, and parents should support a positive body image among teenagers that can motivate them toward developing healthy eating and physical activity habits.

Adolescents who diet in ninth grade were found to be three times more likely than peers to be overweight in 12th grade. Additionally, diets based on calorie-counting may deprive teenagers of the energy required for a normal brain and body growth. Symptoms of anorexia nervosa, which can be a life-threatening condition, could be next.

“It’s not unusual for us to see young people who have rapidly lost a lot of weight but are not healthy; they end up in the hospital attached to a heart monitor with unstable vital signs,” Golden said.

Golden noted that negative vocal observations about the teen’s weight can also be negative to adolescent health because it can lead to poor self image and destructive emotions. Such self dissatisfaction is linked with lower levels of physical activity and with the use of diuretics, laxatives, and vomiting to control weight.

Family meals are a protective strategy against weight problems partly because teenagers can see their parents modeling healthy eating.

The new advice is important because although childhood obesity rates have begun to drop, obesity rates in adolescents have not declined. Helping teens maintain healthy weights without veering toward obesity or an eating disorder is more challenging for teens than it is for young children.

“Adolescents are also dealing with other issues, such as teasing from peers and body-image concerns,” Golden said. “A 3-year-old may not be worried if she’s a bit overweight, whereas an adolescent may try unhealthy weight-loss methods like fasting or diet pills and end up in a vicious circle of more weight gain.”